That is quite a feat, indeed. He could have had a couple of more in yesterday's match.
As for the dilemma, it is unwise to place a universal ceiling on a player's ability to perform based on his age. Some players begin to fall off earlier than others, while others take care of their body in such a manner that permits them to perform for longer. The added experience is a strong contributor to a player's performance, as well.
In other words, the only way to see if Ronaldo could still perform at the World Cup stage, would be to allow him to play in it and observe the results. The manager had all of the data available to him needed to make the decision. We will need to revisit this topic at the end of the tournament and discuss the results.